Swift中的日期格式

Question

我如何从日期转换此日期时间？

由此:2016-02-29 12:24:26发布
于:2016年2月29日

到目前为止,这是我的代码,它返回一个nil值:

let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "MM-dd-yyyy"
dateFormatter.timeZone = NSTimeZone(name: "UTC")
let date: NSDate? = dateFormatter.dateFromString("2016-02-29 12:24:26")
print(date)

Answer 1

您必须声明2个不同的NSDateFormatters,第一个将字符串转换为a NSDate,第二个以您的格式打印日期.
试试这段代码:

let dateFormatterGet = NSDateFormatter()
dateFormatterGet.dateFormat = "yyyy-MM-dd HH:mm:ss"

let dateFormatterPrint = NSDateFormatter()
dateFormatterPrint.dateFormat = "MMM dd,yyyy"

let date: NSDate? = dateFormatterGet.dateFromString("2016-02-29 12:24:26")
print(dateFormatterPrint.stringFromDate(date!))

斯威夫特4:

在斯威夫特3/4 NSDate类已更改为Date与NSDateFormatter对DateFormatter.

let dateFormatterGet = DateFormatter()
dateFormatterGet.dateFormat = "yyyy-MM-dd HH:mm:ss"

let dateFormatterPrint = DateFormatter()
dateFormatterPrint.dateFormat = "MMM dd,yyyy"

if let date = dateFormatterGet.date(from: "2016-02-29 12:24:26") {
    print(dateFormatterPrint.string(from: date))
} else {
   print("There was an error decoding the string")
}

Answer 2

这可能对想要使用dateformater.dateformat的人有用; 如果你想要12.09.18你使用dateformater.dateformat = "dd.MM.yy"

Wednesday, Sep 12, 2018           --> EEEE, MMM d, yyyy
09/12/2018                        --> MM/dd/yyyy
09-12-2018 14:11                  --> MM-dd-yyyy HH:mm
Sep 12, 2:11 PM                   --> MMM d, h:mm a
September 2018                    --> MMMM yyyy
Sep 12, 2018                      --> MMM d, yyyy
Wed, 12 Sep 2018 14:11:54 +0000   --> E, d MMM yyyy HH:mm:ss Z
2018-09-12T14:11:54+0000          --> yyyy-MM-dd'T'HH:mm:ssZ
12.09.18                          --> dd.MM.yy
10:41:02.112                      --> HH:mm:ss.SSS

Answer 3

Swift 4和Xcode 9

let dateFormatter = DateFormatter()
dateFormatter.dateStyle = .medium
dateFormatter.timeStyle = .none
dateFormatter.locale = Locale(identifier: "en_US")
print(dateFormatter.string(from: date)) // Jan 2, 2001

当您想要本地化您的应用程序时,这也很有用.Locale(标识符:)使用ISO 639-1代码.另请参阅Apple文档

Answer 4

使用新Date对象的Swift 3版本NSDate:

let dateFormatterGet = DateFormatter()
dateFormatterGet.dateFormat = "yyyy-MM-dd HH:mm:ss"

let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "MMM dd,yyyy"

let date: Date? = dateFormatterGet.date(from: "2017-02-14 17:24:26")
print(dateFormatter.string(from: date!))

编辑:在mitul-nakum建议之后

Answer 5

斯威夫特 - 4.0

2018年2月2日6时50分16秒+0000转换2018年2月2日

 extension Date {
   static func getFormattedDate(string: String) -> String{
        let dateFormatter = DateFormatter()
        dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss +zzzz" // This formate is input formated .

        let formateDate = dateFormatter.date(from:"2018-02-02 06:50:16 +0000")!
        dateFormatter.dateFormat = "dd-MM-yyyy" // Output Formated

        print ("Print :\(dateFormatter.string(from: formateDate))")//Print :02-02-2018
        return dateFormatter.string(from: formateDate)
    }
}

斯威夫特 - 4.0

2018-02-01T19:10:04 + 00:00转换时间:01年01 月01日

extension Date {
    static func getFormattedDate(string: String , formatter:String) -> String{
        let dateFormatterGet = DateFormatter()
        dateFormatterGet.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"

        let dateFormatterPrint = DateFormatter()
        dateFormatterPrint.dateFormat = "MMM dd,yyyy"

        let date: Date? = dateFormatterGet.date(from: "2018-02-01T19:10:04+00:00")
        print("Date",dateFormatterPrint.string(from: date!)) // Feb 01,2018
        return dateFormatterPrint.string(from: date!);
    }
}

Answer 6

iOS 15.0+

iPadOS 15.0+，

macOS 12.0+，

Mac 催化剂 15.0+，

电视操作系统 15.0+,

watchOS 8.0+，

Xcode 13.0+

使用formatted(date:time:)

let now = Date.now
let date = now.formatted(date: .abbreviated, time: .omitted)

.abbreviated您可以使用其他DateStyle格式（例如 ）来代替.long，.numeric或定义自定义格式。

斯威夫特用户界面

 Text(myDate, format: Date.FormatStyle(date: .numeric, time: .omitted))

或者简单地使用：

 Text(myDate, style: .date)

参考

格式化（日期：时间：）

初始化（_：格式：）

文本.日期样式

Answer 7

迅捷3

let date : Date = Date()
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "MMM dd, yyyy"
let todaysDate = dateFormatter.string(from: date)

Answer 8

Swift 版本：5.6 以上

\n

日期格式化程序 \xe2\x80\x99s dateFormatter 属性用于使用自定义字符串模式格式化日期。

\n

let dateFormatter = DateFormatter()\ndateFormatter.dateFormat = "MMM dd, yyyy"\n    \nlet date = dateFormatter.string(from: datePicker.date)\nprint(date)\n//Feb 28, 2022\n

\n

如果您想要格式化和打印不应\xe2\x80\x99 的任何内容，请在该单词周围使用单引号。喜欢;\xe2\x80\x98at\xe2\x80\x99

\n

dateFormatter.dateFormat = "MMM dd, yyyy \'at\' hh:MM a"\n// May 29, 2022 at 12:05 PM\n

\n

这些都是可能的Format , &模式。DateTimeTime Zone

\n

\n

Answer 9

我用以下方法解决了格式yyyy-MM-dd'T'HH:mm:ss.SSS'Z'（例如2018-06-15T00：00：00.000Z）的问题：

func formatDate(date: String) -> String {
   let dateFormatterGet = DateFormatter()
   dateFormatterGet.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"

   let dateFormatter = DateFormatter()
   dateFormatter.dateStyle = .medium
   dateFormatter.timeStyle = .none
   //    dateFormatter.locale = Locale(identifier: "en_US") //uncomment if you don't want to get the system default format.

   let dateObj: Date? = dateFormatterGet.date(from: date)

   return dateFormatter.string(from: dateObj!)
}

Answer 10

使用额外的格式将 @BatyrCan 答案转换为 Swift 5.3。在 Xcode 12 中测试。

let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "HH:mm:ss"
var dateFromStr = dateFormatter.date(from: "12:16:45")!

dateFormatter.dateFormat = "hh:mm:ss a 'on' MMMM dd, yyyy"
//Output: 12:16:45 PM on January 01, 2000

dateFormatter.dateFormat = "E, d MMM yyyy HH:mm:ss Z"
//Output: Sat, 1 Jan 2000 12:16:45 +0600

dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"
//Output: 2000-01-01T12:16:45+0600

dateFormatter.dateFormat = "EEEE, MMM d, yyyy"
//Output: Saturday, Jan 1, 2000

dateFormatter.dateFormat = "MM-dd-yyyy HH:mm"
//Output: 01-01-2000 12:16

dateFormatter.dateFormat = "MMM d, h:mm a"
//Output: Jan 1, 12:16 PM

dateFormatter.dateFormat = "HH:mm:ss.SSS"
//Output: 12:16:45.000

dateFormatter.dateFormat = "MMM d, yyyy"
//Output: Jan 1, 2000

dateFormatter.dateFormat = "MM/dd/yyyy"
//Output: 01/01/2000

dateFormatter.dateFormat = "hh:mm:ss a"
//Output: 12:16:45 PM

dateFormatter.dateFormat = "MMMM yyyy"
//Output: January 2000

dateFormatter.dateFormat = "dd.MM.yy"
//Output: 01.01.00

//Customisable AP/PM symbols
dateFormatter.amSymbol = "am"
dateFormatter.pmSymbol = "Pm"
dateFormatter.dateFormat = "a"
//Output: Pm

// Usage
var timeFromDate = dateFormatter.string(from: dateFromStr)
print(timeFromDate)

Answer 11

斯威夫特 4、4.2 和 5

func getFormattedDate(date: Date, format: String) -> String {
        let dateformat = DateFormatter()
        dateformat.dateFormat = format
        return dateformat.string(from: date)
}

let formatingDate = getFormattedDate(date: Date(), format: "dd-MMM-yyyy")
        print(formatingDate)

Answer 12

Swift 3带有Date扩展名

extension Date {
    func string(with format: String) -> String {
        let dateFormatter = DateFormatter()
        dateFormatter.dateFormat = format
        return dateFormatter.string(from: self)
    }
}

然后你可以像这样使用它:

let date = Date()
date.string(with: "MMM dd, yyyy")

Answer 13

格式化日期的另一个有趣的可能性。这张截图属于苹果的应用程序“新闻”。

这是代码：

let dateFormat1 = DateFormatter()
dateFormat1.dateFormat = "EEEE"
let stringDay = dateFormat1.string(from: Date())

let dateFormat2 = DateFormatter()
dateFormat2.dateFormat = "MMMM"
let stringMonth = dateFormat2.string(from: Date())

let dateFormat3 = DateFormatter()
dateFormat3.dateFormat = "dd"
let numDay = dateFormat3.string(from: Date())

let stringDate = String(format: "%@\n%@ %@", stringDay.uppercased(), stringMonth.uppercased(), numDay)

洛伦佐利维托提出的替代方案没有什么可补充的。太完美了。

let dateFormat = DateFormatter()
dateFormat.dateFormat = "EEEE\nMMMM dd"
let stringDate = dateFormat.string(from: Date()).uppercased()

Answer 14

如果要从“1996-12-19T16:39:57-08:00”解析日期，请使用以下格式“yyyy-MM-dd'T'HH:mm:ssZZZZZ”：

let RFC3339DateFormatter = DateFormatter()
RFC3339DateFormatter.locale = Locale(identifier: "en_US_POSIX")
RFC3339DateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
RFC3339DateFormatter.timeZone = TimeZone(secondsFromGMT: 0)

/* 39 minutes and 57 seconds after the 16th hour of December 19th, 1996 with an offset of -08:00 from UTC (Pacific Standard Time) */
let string = "1996-12-19T16:39:57-08:00"
let date = RFC3339DateFormatter.date(from: string)

来自 Apple https://developer.apple.com/documentation/foundation/dateformatter

Answer 15

    import UIKit
    // Example iso date time
    let isoDateArray = [
        "2020-03-18T07:32:39.88Z",
        "2020-03-18T07:32:39Z",
        "2020-03-18T07:32:39.8Z",
        "2020-03-18T07:32:39.88Z",
        "2020-03-18T07:32:39.8834Z"
    ]


    let dateFormatterGetWithMs = DateFormatter()
    let dateFormatterGetNoMs = DateFormatter()

// Formater with and without millisecond 
    dateFormatterGetWithMs.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"
    dateFormatterGetNoMs.dateFormat = "yyyy-MM-dd'T'HH:mm:ss'Z'"

    let dateFormatterPrint = DateFormatter()
    dateFormatterPrint.dateFormat = "MMM dd,yyyy"

    for dateString in isoDateArray {
        var date: Date? = dateFormatterGetWithMs.date(from: dateString)
        if (date == nil){
            date = dateFormatterGetNoMs.date(from: dateString)
        }
        print("===========>",date!)
    }